1. Field of the Invention
The present invention relates to an electric operation apparatus which is used in a conductive solution and performs electric operation, e.g., resects, transpires, and discharges and coagulates the body anatomy, and a control method thereof.
2. Description of the Related Art
Conventionally, an electric operation apparatus uses a resectoscope, and is used in a conductive solution and performs electric operation, for example, resects, transpires, and discharges and coagulates the body anatomy.
Generally, the resectoscope is used for transurethral resection and transcervical resection, and mainly comprises an optical scope as an endoscope for observation and an electrode unit for cauterizing the anatomy in an elongated and hollow sheath inserted in the coelom.
Upon observation using the resectoscope, a solution is supplied in the coelom through the sheath and the field of view is ensured.
Conventionally, the solution supplied to the coelom is a non-conductive D-sorbitol solution or the like. High-frequency current is collected by a collecting electrode which is extracorporeally arranged via the electrode and the body anatomy.
Here, in the conventional electric operation apparatus, the high-frequency current stimulates the nervus, thereby causing the muscular reflex.
Thus, the conventional electric operation apparatus needs the blocking of high-frequency current against the nervus. The D-sorbitol solution is not supplied in the coelom for a long time and therefore the operation time is limited.
In order to solve the above-mentioned problems, Japanese Unexamined Patent Application Publication No. 2000-201946 discloses a technology which uses physiological saline, as the conductive solution, that is sent to the coelom of the body for a long time, collects the high-frequency current by using the sheath in place of the collecting electrode, and reduces the stimulation of nervus.
Further, U.S. Pat. No. 5,697,281 discloses a technology which applies electric energy to a target position in the body or of the structure on the body by applying a high-frequency voltage between an electrode terminal and a return electrode.